This invention relates to a new and improved adjustable vehicle seat mounting mechanism and particularly to a seat suspension system which provides for adjusting and locking modes as well as an isolation mode permitting limited oscillatory movement of the seat.
Conventional adjustable seat devices generally include a pair of laterally spaced, supporting apparatus having an individual latching mechanism interconnected between the supporting apparatus and operatively connected to a release handle. The supporting apparatus often takes the form of an upper support attached to the seat assembly, a lower support fixed to the floor of the vehicle and some type of slide mechanism interconnecting the upper and lower supports for forward and backward movement relative to the vehicle. A latch mechanism associated with the supporting apparatus permits the upper and lower supports to be locked in a position selected to accommodate the physical characteristics of the occupant of the seat.
Normally, a slide assembly interconnects the upper and lower support members. The slide assembly usually comprises a pair of cooperating, elongated U-shaped slide members having laterally formed portions of their sidewalls interconnected to one another by ball or roller bearings arranged to provide relatively frictionless adjustment.
Some seat mounting devices of the character described include means commonly referred to as fore and aft isolators which permit the vehicle seat to move both forward and backward to a limited degree under the control of a spring system in response to vehicle vibration. Such isolators are operative in the locked mode of the seat suspension system and accommodate vehicle vibration to partially isolate the seat occupant from such vibration.
An example of a vehicle seat suspension system which incorporates an isolator device is shown in U.S. Pat. No. 3,258,241 to W. C. Oswald, dated June 28, 1966. In that patent, a vibrationally isolated vehicle seat suspension is disclosed and includes means which will render the isolation mechanism inoperative by directly connecting the vehicle seat to the base at a predetermined fore and aft position of the seat. Known isolators as exemplified by Oswald have a number of drawbacks or problems. For instance, plural control handles or levers are required to fully operate the seat suspension system. One control is provided for fore and aft seat adjustment locking, and a second control is provided for activating or conditioning the isolator mechanism. This may be confusing to the occupant of the seat. In addition, one of the controls does not move with the seat as the seat is adjusted. This may prove hazardous when the occupant tries to locate a control handle which should desirably move with the occupant as the seat is adjusted.
A need, therefore, exists for an adjustable vehicular seat mounting device which incorporates an isolator mechanism wherein the adjusting, locking and isolation modes of the device are controlled by a single hand lever and wherein the control lever moves with the seat and occupant.